Russian warplanes have arrived home from Syria as opposition negotiators demanded the Government detail its thoughts on a political transition.
The planes left after Moscow on Tuesday said it would start to withdraw forces. Russia has tipped the war President Bashar al-Assad's way.
The development came as peace talks were being held in Geneva. The opposition High Negotiations Committee used its first meeting in the round of peace talks to give United Nations mediator Staffan de Mistura a set of general principles to guide the transition, a process to be overseen by Russia and the United States in line with a UN resolution.
"We intend to go into detail. We intend to go fast. We would like to see this process make progress very quickly," HNC member Basma Kodmani said after the meeting.
She said the delegation had raised concerns about the humanitarian situation, particularly in the towns of Daraya, where "after four years there still is no aid at all that has gone in", and Al Waer in Homs governorate.